Entrepreneur and GoDaddy spokeswoman Danica Patrick recently released a book in 2017 called “Pretty Intense,” about a 90-day plan promising to change your life.

So what does it take to be physically fit?

“It’s about intensity. It’s about pushing yourself. It’s about pushing your boundaries,” Patrick said Monday afternoon at Business Insider’s IGNITION Conference in New York City during a conversation with BI’s chief tech correspondent Julie Bort.

“It’s really that simple,” Patrick continued. “It will be amazing, the effects, when you push yourself physically, that it has on your life otherwise. Whether it’s your confidence, your job, you name it.”

The former race car driver shared she put 100% of herself into the book, writing the recipes, designing the cover, taking the food photos, and more. Patrick listed off several workouts that are part of a fit test in her book, including 100 sit-ups and 100 knee push-ups back-to-back.

PenguinThe cover of Danica Patrick’s 2017 book, ‘Pretty Intense.’

“You say to yourself, ‘I can’t do that.’ And then you do it and you start saying ‘I can’ so much more often. You build that confidence and that positivity,” said Patrick. “It’s about pushing yourself. For me, it didn’t happen until I started doing crossfit about five or so years ago, and I was like, ‘Oh, that’s working out!'”

Patrick then asked the audience a question that caught them off guard a bit.

“Has anyone worked out so hard that you feel like you taste blood?” Patrick said to laughter from the crowd. “There’s apparently fluid in your lungs. I’m just going to tell you that you can make that happen in about two minutes or less. Anyway, it taught me about intensity.”

Business InsiderDanica Patrick asks the crowd if they have ever worked so hard that they have had the taste of blood in their mouth.

Bort asked whether or not that was how Patrick got in the shape that she is on the cover of her 2017 book, she said it was that and dieting.

“Abs are made in the kitchen and there’s no way around that. I’m sorry, but that’s true,” she said. “I had finally done a workout program, which was intensity and integral training along with a different diet. I had the best results, which is why I ended up writing the book and wanted to help people to share what I had experienced for myself so this book was my baby.”